In the past, infectious diseases have been widespread in developing countries and chronic diseases were found primarily in high income countries. However, the global pattern of disease burden is shifting. While infectious disease still remains a major problem in many countries, chronic diseases, including such noncommunicable conditions as cardiovascular disease, cancer, diabetes and respiratory disease, are now the major cause of death and disability, not only in developed countries, but also worldwide.
The greatest total numbers of chronic disease deaths and illnesses now occur in developing countries.
Non-communicable diseases (NCDs), such as cancer, heart disease, lung disease, and diabetes, are now the major cause of death and disability worldwide. By 2020, NCDs are expected to account for 7 of every 10 deaths in the world, as they already do in some 'developed' countries. These projections suggest that NCDs and the death, illness, and disability they cause will soon dominate health care costs and are causing public health officials, governments and multinational institutions to rethink how we approach this growing global challenge.
According to statistics from the World Health Organization, non-communicable diseases are responsible for 63% of deaths worldwide, double the number of deaths from infectious diseases (including HIV/AIDS, tuberculosis, and malaria), maternal and perinatal conditions, and nutritional deficiencies combined. The principal known causes of premature death from NCDs are tobacco use, poor diet, physical inactivity, and harmful alcohol consumption.
Although NCDs make up a greater proportion of deaths and illnesses in developed countries, overall the greatest numbers of non-communicable disease deaths and illnesses occur in the developing world. Eighty percent of NCD-related deaths worldwide occur in low- and middle-income countries.
Apart from the tremendous adverse effects on the quality of life of individuals involved, these conditions place enormous strains on family and community budgets. The overall economy suffers from both the labor units lost due to death and illness as well as the high direct medical costs. This phenomenon, during which health infrastructures already weakened by continuing battles with infectious disease are increasingly being taxed by rapidly growing NCDs, is often referred to as the double disease burden.